Direct conversion of carbonaceous material to hydrocarbons



April 7, 1970 3,505,204

DIRECT CONVERSION OF CARBONACEOUS MATERIAL TO HYDROCARBONS Filed Aprill0, 1967 E. J. HOFFMAN 2 Sheets-Sheet l wDZDOa s OO ucsoaoo 58 S522.:

ATTORN E YS April 7, 1970 E. J. HOFFMAN 3,505,204

DIRECT CONVERSION OF CARBONACEOUS MATERIAL TO HYDROCARBONS Filed AprillO. 1967 2 Sheets-Sheet 2 Product Stream IO 7 Il FIXED FIXED BED BEDREACTOR REACTOR (A) (B) vv w@ 8 9 Steam Steam Product MOVING BED S"'e" gReacted REACTOR 4Unreucted iCarbon aceous Carbonaceous Material MaterialINVENTOR EDWARD J. HOFFMAN BYCSSQ QQQ/ QQ//W ATTORNEYS` United StatesPatent O 3,505,204 DIRECT CONVERSEION F CARBONACEOUS MATERIAL T0HYDROCARBONS Edward J. Hoffman, Laramie, Wyo., assignor to TheUniversity of Wyoming, a body corporate of Wyoming Filed Apr. 10, 1967,Ser. No. 629,498 Int. Cl. Cg 1/08 U.S. Cl. 208-10 16 Claims ABSTRACT 0FTHE DISCLOSURE Coal 0r other naturally occurring bituminous carbonaceousmaterials, or carbon, coke, or carbonaceous petroleum materials areconverted directly to hydrocarbons and oxygen-containing organiccompounds by reacting the carbonaceous material with steam in thepresence of a two-component catalyst system. The rst catalyst componentis a compound of an alkali or alkaline earth metal and the secondcomponent is a compound of a group 8 transition metal. By utilizingthese catalysts, good yields of hydrocarbons are obtained in a singlestage reaction at temperatures of from 800 to 1000 or 1200 F.

The present invention relates to methods of converting carbonaceousmaterials to hydrocarbons. More particularly, the invention relates to amethod of directly converting carbonaceous materials to hydrocarbons byreaction with steam. Still more particularly, the invention relates tomethods of directly converting materials such as coal and naturallyoccurring carbonaceous materials to hydrocarbons and oxygen-containingorganic materials in a onestage reaction with steam.

The desirability of converting coal and other hydrogendeficientcarbonaceous materials to hydrocarbons has long been recognized. It hasbeen recognized, for example, that economical conversion of cheapcarbonaceous materials to relatively expensive organics such as gasolinewould be a signicant achievement in view of the vast deposits of suchcarbonaceous materials such as oil shale and oil sands. In the past,efforts toward the chemical conversion of carbonaceous materials, asexemplied by coal, have been directed to two principal methods: directand indirect hydrogenation.

fIn direct hydrogenation, the coal is reacted with hydrogen at moderateto severe conditions of temperature and pressure. The product isdetermined by the reaction conditions, catalyst, and space velocity orresidence time. Processing may be batch or continuous. Directhydrogenation of coal was accomplished as early as 1913. Ordinarily aliquid carrier is used to contain the coal (and catalyst), and thecarrier participates in and modifies the hydrogenation reactions. Whiledirect hydrogenation has been applied commercially, the expense ofhydrogen and the rather severe operating conditions have been seriousproblems.

Indirect hydrogenation refers to the production of a synthesis gas fromcoal (or other sources) followed by the reaction of the synthesis gasover a suitable catalyst to form hydrocarbons as well as oxygenatedorganic compounds.

The synthesis gas which is produced by the reaction of the carbonaceousmaterial and steam, consists of a mixtre of carbon monoxide and hydrogenof varying proportions, which also influences the nature of the product.The reaction of the synthesis gas to hydrocarbons is generally calledthe Fischer-Tropsch reaction. Reaction conditions are considerably lesssevere than for direct hydrogenation.

The production of synthesis gas may be performed by any of the severalconventional water gas processes, in

which coal (carbon) and steam react by the water gas reaction to producewater gas, an equimolar mixture of hydrogen and carbon monoxide:C-|-H2O- CO-i-HZ. The percentage hydrogen may be increased by addingsteam and passing the mixture over a suitable catalyst to yield morehydrogen by the water gas shift:

In this way virtually all hydrogen can be produced for use in, say,direct hydrogenation. Synthesis gas (and also hydrogen, via theCO-shift) is also produced from natural gas (essentially methane) bysteam reforming or partial oxidation.

The production of synthesis gas from coal is a high ternperatureendothermic reaction requiring the addition of a good deal of heat tosustain the reaction. This has led to several means for contributingheat to the reaction. Cyclic processes air-oxidize the bed of coal to asuitable temperature level, then introduce steam. Continuous processesgenerally introduce pure oxygen in the proportions to sustain thereaction temperature. All means contribute considerably to the expense.

The reaction of synthesis gas is a low temperature eX- othermic reactiongiving ol heat. This requires that heat be removed from the reactingsystem, which contributes greatly to the cost, especially since acatalyst is involved. Chieily for cost reasons, hydrocarbon productsproduced by direct or indirect hydrogenation from coal and othercarbonaceous materials have not been economically cornpetitive withpetroleum-derived products.

It is an object of the present invention to provide a process for thedirect conversion of carbonaceous materials into hydrocarbons. It is afurther object of the invention to provide such a process Widelyapplicable to carbonaceous materials such as naturally occurringcarbonaceous deposits, and other carbon-containing materials such ascarbon, coke, petroleum fractions, etc., capable of hydrogenation. It isstill a further object of the invention to provide an economical processof the type mentioned and to such processes which are applicable to thecarbonaceous materials either in situ in their naturally deposited stateor in a reactor. It is still a further object of the invention toprovide such methods which are 0perable under relatively mild operatingconditions and which yield hydrocarbons and/or oxygenated organiccompounds in good yield. These and other objects which will becomeapparent in view of the detailed description following are achievedaccording to the invention by reacting the carbonaceous material withsteam in the presence of a two-component catalyst system to be describedmore fully in the detailed description which follows and which includesthe drawings wherein:

FIGURE 1 is a ow sheet diagram of a method according to the inventionutilizing a fluidized bed reactor; and

FIGURES 2 and 3 are diagrams of alternative types of reactors.

By the use of a suitable two-component catalyst system according to theinvention, it is possible to reduce the temperature levels of theinitial car-bon steam reaction to those for the Fischer-Tropschreactions, thus making possible the direct, single stage overallconversion with the attendant savings in investment and processingcosts. The endothermicity of the initiation reactions tends to bebalanced by the exothermicity of the completion reaction, thuseliminating most of the heat transfer problems ordinarily encountered.

In this process, carbonaceous material and steam are reacted in a singlestage reactor, A multiple catalyst is also present in the reactor, andcan be introduced pulverized or in a slurry. The reactor is operable inthe temperature range of approximately 800-1200" F., and at pressures offrom near atmospheric to around 500 p.s.i., depending upon the nature ofthe product desired, The overhead product from the reactor is passedthrough a solid-gas separator to remove entrained solids, and thenpartially condensed to yield a hydrocarbon phase and an aqueous phasecontaining predominately the oxygenated compounds, though some are alsopartitioned in the hydrocarbon phase. The uncondensed vapors contain themore volatile hydrocarbons (principally methane, ethane, ete), as wellas carbon dioxide.

The gaseous product may be treated for CO2 and HZS removal and processedfor LPG (liquied petroleum gas, usually propane and butane) and forrecovery of any gasoline fractions also present. The sulfur content willvary depending upon the coal used. The gases may be partly recycled tothe reactor (before or after CO2 recovery) as a means of suppressing gasformation and for reactor temperature control.

The condensed hydrocarbon liquid phase may be further rened according toconventional refinery procedures to yield gasoline and diesel fuels, andhigher molecular weight residues. Some gas and LPG will also bedissolved in the liquid layer, depending upon the phase equilibria ofthe separation. The aqueous layer will contain principally dissolvedoxygenated compounds such as the lower alcohols, aldehydes and ketones,and organic acids, These may be subjected to further separation by meansof the techniques of azeotropic and extractive distillation, solventextraction, etc. The aqueous layer can be recycled as a source of steamfor the reaction and uidization. If all or part of the oxygenatedcompounds are left in the recycle, these compounds will act to suppressfurther oxy formation.

The catalyst system includes two components. The first component is acompound of an alkali metal or an alkaline earth metal. Oxides andcarbonates of sodium and potassium are preferred, but other compounds,such as chlorides, hydroxides, sulfates, silicates, suldes, etc., can beused. The compounds can be used directly in an impure state. Forexample, the hydrated sodium carbonate ore, trona, can `be useddirectly. The second catalyst is a Fischer-Tropsch type catalystcontaining a transitional metal of group 8 of the Periodic Table.Compounds of iron, nickel and cobalt are preferred, and of these, ironcompounds, particularly the iron oxides, are the most preferable. Othermetals belonging to the group are Ru, Rh, Pd, Os, Ir and Pt. Thecompounds may be oxides or other compounds such as carbonates, nitrates,carbides, chlorides, sulfates, etc., and the second component mayinclude compounds of metals in different valence states. For example,the second component may comprise vferrous and ferrie oxide. The secondcomponent need not be pure. Iron catalyst, for example, may consist ofnitrided steel wool, steel turnings, iron ore, roasted pyrites, fusediron, mill scale, iron alloys, steel shot, lathe turning magnetite,hematite, Luxmasse, Lautamasse, siderite, goethite, ferrosilicon,limonite, and sandstone (with Fe present). The more active catalysts forthe completion of the reaction would be Ni or Co. However, these are notonly more expensive than Fe, but are quite reactive at the reactorconditions, and tend to produce gases (greater degree of hydrogenation)preferentially to liquids. The nickel and cobalt will also tend to belost from the system due to the production of volatile car- Ibonyls.

The first and second catalyst components may each comprise one or moreof the mentioned compounds and, it is preferred that the secondcomponent comprise tow similar compounds, such as oxides, of the samemetals, but at different valence states. The relative amount of eachcomponent can vary Widely. Generally speaking, however, the system willcontain from to 7 5 by weight of the rst component and preferably aboutl0 to 50%.

The carbonaceous material, steam and catalyst system are broughttogether in a reaction zone which may be provided in situ in a naturaldeposit of carbonaceous material or in a reactor. Several types ofreactors, such as a xed bed or moving bed type can be used, but afiuidized bed reactor is preferred. The amount of steam provided forreaction can vary widely depending on desired results. Higher steam tocarbon ratios cause a greater amount of hydrogenation and production ofmore lower molecular weight compounds. However, generally speaking, theratio of steam to carbon, on a weight basis will ordinarily be betweenl/4 and 5/1 and preferably between 1/2 and 3/ 1.

The temperature of the reaction is maintained at 800 to 1200 F.,preferably 800 to 1000 F. The temperature is conveniently maintained byintroducing superheated steam to the reaction zone. Higher temperaturesincrease the yield, but favors the production of gaseous and lowermolecular products and oxy compounds. The steam can be superheated toany suitable extent to provide extra heat as necessary for the process.Excess steam can be utilized to provide the same effect. ln all of theprocesses according to the invention, excess steam has a beneficialdistilling effect. Excess heat can also be provided by the addition ofoxygen to the reaction and this is particularly useful in the in situreaction. The steam temperature is conveniently between 800 F. and 140()F. or higher. The steam temperature will ordinarily be in excess of1000o F., particuarly in the in situ process.

The pressure can vary widely. Pressures of under 200 p.s.i. arepreferred, but higher pressures of up to 500 p.s.i. are feasible.Pressures of over 300 p.s.i. favor the production of lower molecularWeight hydrocarbons. Lower pressures favor the -production ofhydrocarbons, but reduce conversion or require the use of more catalyststo obtain good yield. Substantially atmospheric pressure is necessarilyutilized in an in situ operation but a minimum pressure of about 15p.s.i. is preferred for reactor operations to achieve good yield andcatalyst economy. By operating at pressures of from l5 to 30 p.s.i,conventional petroleum processing equipment can be `utilized andpractical yields obtained.

The carbonaceous materials to which the invention is applicable varywidely in nature and composition. However, it can be generally said thatthe carbonaceous material is hydrogen decient and thus capable of beinghydrogenated to hydrocarbons. The principal materials occur in naturaldeposits, but the invention is also applicable to carbonaceous productssuch as carbon, coke and petroleum fractions. The naturally occuringcarbonaceous deposits to which the invention is applicable includefossil fuels such as peat, coal, gilsonite, oil shale, oil or tar sandsand other natural deposits of bituminous material including very lowgrade materials combined with substantial amounts of inerts. Coals ofany grade, such as lignite, bituminous and anthracite, are readilyhydrogenated according to the invention.

Where a reactor is utilized, the carbonaceous material may be pulverizedand/or heated prior to effecting the reaction with steam. Preheatinghelps to maintain eicient reactor temperature conditions and isparticularly effective where the carbonaceous material contains asubstantial amount of water. Since the reaction requires bringingtogether steam and carbonaceous material, reducing the particle size orthe carbonaceous material is obviously desirable. Where the reactor isof the fixed or moving bed type, substantially any size material can beused. In a fluidized system, the particle size can vary Widely, betweenlimits of practical fluidizing requirements known as such to those ofordinary skill in the art. Generally speaking, however, the carbonaceousmaterial in nidized bed reactors will be between 200 Tyler mesh and 1/2inch. The size of the catalyst particles are scaled to the carbonaceousmaterial size according to Stokes law calculations and can vary quitewidely from theoretical since it is not required that the residence timeof the catalyst and carbon material be the same. Generally speaking,however, the particle size of the second catalyst can vary from about200 mesh to about 1/z inch. The rst catalyst component is frequentlywater soluble and can be introduced to the reactor in solution form inwhich case the particles thereof will generally be quite small. However,if the first component is used in solid form, it will also beconveniently used in a size range of from about 200 mesh to about 1/2inch.

The reaction time can vary widely. Shorter times favor the production oflower molecular weight hydrocarbons. The reaction time in reactorsystems usually incorporates reactor sisze and feed rate and is referredto as residence time or space velocity and is dened as follows:

1 Residence time Residence time (h1`)= Space velocity (hn-1) Thereaction according to the invention is initiated almost instantaneouslyand long residence times do not eliminate hydrocarbons from the reactionzone. Accordingly, the residence time can be varied as desired. Typicaloperating values are mentioned in the example which follows.

With reference to FIGURE 1, an operation utilizing a uidized bed systemwill be described in detail. Coal pulverized to an average particle sizeof 35 mesh (Tyler) on a roller mill is prheated to a temperature ofabout 800 F. and continuously introduced into a fluidized bed reactorsuch as a simple refractory-lined column including means to introduce afluidizing gas. Steam is introduced into the coal feed stream 1 and is4used to -motivate the coal into the reactor. Pulverized catalyst isintroduced to the reactor and additional steam is used to motivate thecatalyst through feed stream 2. The catalyst contains about by weightsodium carbonate of an average size of 65 mesh and 90% impure iron oreof an average size of about 40 mesh made up of Fe304, Fe203, FeO, Fe,and other materials, principally iron carbides. About 40% of thecatalyst is in a reduced state which state can be achieved by subjectingspent caalyst to a regenerating step to be described subsequently. Steamis introduced at a rate of aboutl.5 moles per mole of carbon to maintainuidized conditions at space velocities to 400 hr.-l and the reaction ismaintained at a temeprature of from 800 to 1000 F. at a pressure of from10() to 200 p.s.i. Steam can also be introduced directly to the reactorat 3 as shown in FIG- URE 1. The catalyst may conveniently be groundwith the carbonaceous material and introduced into the reactor throughthe same feed stream and, of course, the catalyst may be pre-heated.

Solids are separated from the overhead stream 4 by one or more cycloneseparators. Other separators can be used and provision can be made toremove solids from a point below the top of the reactor which may bedesirable in the event that the carbonaceous material includes a gooddeal of inert substances. Solids removed from the overhead includecatalyst, unreacted coal, ash, and any inerts not otherwise separatedfrom the reactor. The solids may be recycled to the reactor unless theyinclude a substantial amount of inerts in which case these materials areseparated in any convenient manner such as by fluidizers and the like.If the iron catalyst is recycled, it may require regeneration in whichcase the catalyst, together with unreacted coal, is treated withhydrogen or synthesis gas at temperatures of from 50G-700 F. or higher.

The gaseous overhead is partially condensed to form a liquid stream 5and a gaseous overhead stream 6. The gaseous stream includes CO2, C1,C2, LPG and H2S. This stream can be treated to remove CO2 and HZS andprocessed for the LPG and other hydrocarbons present. The stream may bepartially recycled to the reactor before or after CO2 removal tosuppress gas formation in the reactor and to provide temperaturecontrol.

The liquid product stream 5 contains an aqueous fraction and ahydrocarbon fraction which are mutually insoluble and thus easilydivided. The hydrocarbon fraction may be refined by conventional reneryprocedures to yield gasoline, diesel fuel and other useful petroleumfractions. The aqueous layer will include oxygenated compounds such asalcohols, aldehydes, ketones, acids and the like which are valuable inthemselves and can be recovered by conventional separation techniquessuch as distillation. The aqueous fraction can be recycled to thereactor as a source of steam. Any oxygenated compounds present in thestream will act to suppress further generation thereof in the reactor.

The process conditions can be varied in one or more Ways to favor theproduction of hydrocarbons over these oxygenated compounds or viceversa. Accordingly, while the instant example illustrates an operationfavoring hydrocarbons, the process could be operated at lowertemperatures and increased pressure to favor the production ofoxygenated compounds.

For the illustrated pro-cess, a representative yield based on lbs. ofcarbon reacted (exclusive of carbon shift) is shown in the followingtable:

Product Weight Percent of product CO2 29. 1 19. l C1 and C2. 32. G 21. 3G 5. 3 3. 5 Polymer gasoline. 23.1 15.2 Straight run gasoline 32. 3 2l.2 4. 6 3. 0 2. 3 l. 5 23. 8 15. 2

Approximately one-third of the total carbon reacted goes to CO2 via theCO-shift. Overall carbon conversion is around 77%.

Alternative reactor systems can be used. For example, a fixed bedreactor system as shown in FIGURE 2. can be utilized. In this system,the carbonaceous material and catalyst are provided in one or more xedbed reactors in the form of a column or tank. Two such columns (A) and(B) are shown in FIGURE 2. Steam is introduced to the reactor and thegaseous overhead stream 7 is analogous to stream 5 as shown in FIGURE l,but may contain some fine entrained solids in which case a separator canbe used as shown in FIGURE 1. The catalyst, or a part thereof, may beintroduced entrained in the steam. The spent reaction mass is eventuallydischarged from the reactor and, after regeneration of the catalyst, itmay be recycled for further reaction. A plurality of reactors are usedto provide a continuous operation. For example, in the two-column systemshown in FIGURE 2, valves 8 and 10 are opened to permit steam to enterreactor (A) and to obtain a product stream 7 from the reactor. Duringthat time, valves 9 and 11 are closed, and reactor (B) can convenientlybe emptied and re-illed with a fresh charge. The procedure is alternatedto provide continuous evolution of product stream 7. While only tworeactors are shown, it will be understood that many more could beutilized.

A moving bed reactor, such as that shown in FIGURE 3, can be utilized.In this device, a bed of solid carbonaceous material is moved throughthe reactor. Steam is introduced to the reactor and may iiowcounter-current to the moving bed as shown, or may ow con-currenttherewith in a fashion analogous to the fluidized reactor of FIGURE l.In this embodiment, at least part of the catalyst system is preferablymixed and carried with the solids on the moving bed, but some or all ofthe catalyst may be introduced entrained in the steam.

As mentioned above, the method is also applicable to petroleumfractions. For example, waxy or oily petroleum fractions can behydrogenated as can lighter fractions. These materials can be introducedas such into the reactor, in which case they would be de-volatilized atreactor conditions to yield a coke-like material and the coke materialwould undergo a reaction like that described for coal. Coke derived fromany source, such as from coal or from processing of these petroleummaterials, can also be introduced as such into the reactor and suchpre-treatment of the petroleum materials constitutes a convenient way ofproviding the raw material in a iinely divided state.

The invention is also applicable to the in situ processing of depositsof coal, oil shale, oil or tar sands, or other natural formationsbearing carbonaceous and hydrogen deficient materials of varyingcarbon/hydrogen content. This includes formations of low API gravitypetroleum. The operation is based upon the principles for the direct,single stage reactor conversion process described above. However,instead of the reacting system being confined to a fabricated reactor,the formation bearing the fossil fuel forms the reactor.

Superheated steam is introduced into the formation, with appropriatedissolved or entrained catalysts, and both reacts with and distills thecarbonaceous materials and products from the formation. The processes ofdecomposition and devolatilization occur along with the reaction of thesteam and the distillation of the system. The steam also serves to heatthe formation and melt the more readily liquefiable portions of thecarbonaceous materials. To augment the heating action of the steam, theformation may be heated by partial combustion by cycling with air.Oxygen could also be added with the steam, but this is not recommendeddue to cost considerations. Still other means of supplying heat (andfracture) would be the use of explosions such as nuclear explosions, orother methods.

The use of an alkali metal carbonate forms a significant feature of theprocess. The presence of an alkali carbonate catalyst, such as sodiumcarbonate, permits the steam to react with the carbonaceous material attemperatures as low as of the order of l000 F. This is particularlyimportant in this in situ-process due to the necessity of heating theformation which may include a substantial amount of inerts.

The catalyst may be introduced with the steam. However, in someformations (such as Green River shale) alkali metal carbonate catalystssuch as trona and nahcolite may be present which would reduce the amountof the first catalyst component required to be added. The Fischer-Tropsch catalyst is also added with the steam, but may be added in anamount reduced due to the presence of suitable catalysts naturallypresent. Green River shale, for example, contains some iron carbonates.As in the reactor operations, the preferred Fischer-Tropisch catalyst isa mixture of metal compounds of different valence states such as mixedferrous and ferric oxides or carbonates.

The resulting overall product will be hydrocarbon and oxygenatedcompound mixture plus unreacted carbonaceous materials from theformation. The products exhibit a Wide disparity in volatility, from thelight hydrocarbons down to high molecular weight compounds. Athree-phase product mixture can result: a gas phase, an essentiallyhydrocarbon liquid phase, and a water-phasedepending on conditions. Thegas phase may be considered at its dew point and will carry smalleramounts of the higher molecular weight materials. The hydrocarbon liquidphase, at its bubble point, will contain some dissolved gases, and itsextent will depend upon conditions of temperature and pressure.

A condensed water phase may or may not exist depending upon conditionsof temperature and pressure. If present, there will be containeddissolved oxygen compounds. The presence of H2O in the system acts as anazeotrope former to enhance the distillation into the vapor phase of theless volatile material, It is not necessary for a part of the water toexist as a condensed phase for this action to occur. And in the presenceof sufficient H2O, all identiable liquids would tend to exist in thevapor phase as an azeotrope.

By adjusting processing rates, and the location of injection andrecovery, any liquids present can be removed entrained with the vaporphase. Injection and recovery may be at the same point: for instance,using concentric lines for the steam injection and for product. Or,separate injection and recovery lines can be used. Successfulapplication of the latter requires that an initial contact be madebetween injection and recovery-by fracture, or otherwise. The operationwill of course be enhanced by the insulation of the injection andrecovery lines.

The recovered combined product may be refined by the conventionalprocedures to separation, treating, conversion, etc. The effluent streamwould be partially condensed to form a gas phase, hydrocarbon richliquid, and an aqueous phase. The gas phase is predominately of thelight hydrocarbons and carbon dioxide. The aqueous phase contains mostof the oxygenated compounds. The gas phase should be treated for CO2 andHZS removal, and a part may be recycled with the inlet steam. Recyclewould tend to suppress further hydrocarbon gas formation, and provides astripping action in the formation. The gas recycle could be preheated toreaction conditions. The aqueous phase can be distilled to recover apart of the oxygenated compounds and then recycled to the steamgenerator. The presence of some oxygenated compounds would tend tosuppress Oxy formation in favor of other reaction sequences. Thespectrum of product distribution is similar to that for above-groundprocessing in a fabricated reactor.

From the foregoing, it will be seen that the invention provides a singlestage conversion of carbonaceous materials to hydrocarbons in goodyield. Oxygenated organic compounds can also be produced in good yield.The process involves the use of a two component catalyst system, bothcomponents of which can comprise very inexpensive materials and can beeasily recycled. Accordingly, the process provides an inexpensive methodof producing hydrocarbons, such as gasoline, from carbonaceous rawmaterials.

What is claimed is:

1. A method of producing hydrocarbons directly from solid or liquidcarbonaceous material which comprises: introducing said carbonaceousmaterial and a gas reactant feed stream into a reaction zone, said gasreactant consisting essentially of steam and being introduced in anamount of from 0.25 to 5` moles per mole of carbon contained in thecarbonaceous material introduced into the reaction zone; providing insaid reaction zone a multicomponent catalyst system containing at leastone first catalyst component selected from the group consisting ofalkali and alkaline earth metal compounds, and at least one secondvcatalyst component selected from the group consisting of group 8transitional metal compounds; maintaining said reaction zone at atemperature of from 800 to 1200 F. and a pressure of up to 500 p.s.i.;and removing from said reaction zone a product stream containinghydrocarbons produced in said reaction zone.

2. A method according to claim 1 wherein said carbonaceous material issolid and is selected from the group consisting of fossil fuels andcoke. j

3f. A method according to claim 1 wherein said carbonaceous materialcomprises at least one bituminous material selected from the groupconsisting of coal, peat, lignite, gilsonite, oil shale, oil sand andtar sand.

4. A method according to claim 1 wherein said carbonaceous materialcomprises coal.

5. A method according to claim 1 wherein the reaction is carried out ata temperature of from 800 to 1000 F.

6. A method according to claim 1 wherein the reaction is carried out ata pressure of less than 300 p.s.i.

7. A method according to claim 1 wherein the first catalyst componentcomprises at least one member selected from the group consisting ofoxides and carhonates of alkali and alkaline earth metals.

8. A method according to claim 1 wherein the second catalyst componentcomprises at least one member selected from the group consisting ofoxides of iron, nickel and cobalt.

9. A method according to claim 1 wherein said carbonaceous material is anatural deposit of a bituminous material and wherein the reaction iseffected by introducing superheated steam at a temperature of at least1000o F. and said catalyst system simultaneously into said deposit toeffect said reaction in situ.

10. A method according to claim 1 wherein said reaction is effected byintroducing particles of said carbonaceous material into a reactionzone, providing particles of said rst and second catalyst components insaid reaction zone, introducing a uidizing gas comprising said steam toform a iluidized bed of said carbonaceous and catalyst particles in saidzone, maintaining the ternperature in said zone at from 800 to 1200 F.,withdrawing a product stream from said zone comprising hydrocarbonproducts formed during the reaction, and separating at least one of saidhydrocarbon products from said product stream.

11. A method according to claim 1 wherein said carbonaceous material andcatalyst are provided in a reaction zone in the form of a Xed bed, saidmethod further comprising withdrawing a product stream comprisinghydrocarbon products formed during said reaction from said reactionzone, and separating at least one of said hydrocarbon products from saidproduct stream.

12. A method according to claim 1 wherein the rst component of saidcatalyst system is present in an amount of from 5 to 75 parts by weightper 100 parts of said system.

13. A method according to claim 1 wherein the catalyst systern ispresent in an amount of from 10 to 200 parts by weight per 100 parts byweight of the total amount of carbon in said carbonaceous material.

14. A method according to claim 1 wherein a bed of said carbonaceousmaterial and catalyst is moved through a reaction zone, and `whereinsaid steam is introduced into the reaction zone, further comprisingwithdrawing a product stream comprising hydrocarbon products formedduring said reaction from said reaction zone, and separating at leastone of said hydrocarbon products from said product stream.

15. A method according to claim 8 wherein the rst catalyst component isselected from the group consisting of oxides and carbonates of alkalimetals.

16. A method according to claim 1 wherein a portion of the productstream is recycled to the reactor.

References Cited UNITED STATES PATENTS 1,890,434 12/1932 Krauch et al208-10 3,252,773 5/1966 Solomon et al 48-202 2,657,124 10/1953 Gaucher208-8 DELBERT E. GANTZ, Primary Examiner V. OKEEFE, Assistant ExaminerU.S Cl. XR.

